Rayleigh scattering is used for applications requiring elastic scattering of light, such as atmospheric studies and understanding light scattering in gases. In contrast, Raman scattering, which involves inelastic scattering, is applied in molecular spectroscopy to gain insights into molecular vibrations and chemical composition. The choice between elastic and inelastic scattering depends on the information needed from the interaction with photons. Understanding the context of the incident light or single photon is crucial for selecting the appropriate scattering method. Both techniques serve distinct purposes in scientific research and analysis.